I think you need to do it manually, the line wrap is only visiual.

Sent from my iPhone

On Jul 8, 2013, at 4:00 AM, Aran Wilkinson <notifications@github.com> wrote:

> In _posts/07-02-01-Errors.md:
> 
> > @@ -0,0 +1,11 @@
> > +---
> > +isChild: true
> > +---
> > +
> > +## Errors {#errors_title}
> > +
> > +PHP has several levels of error severity. The three most common types of messages are errors, notices and warnings. These have different levels of severity; `E_ERROR`, `E_NOTICE`, and `E_WARNING`. Errors are fatal run-time errors and are usually caused by faults in your code and need to be fixed as they'll cause PHP to stop executing. Warnings are non-fatal errors, execution of the script will not be halted. Notices are advisory messages caused by code that may or may not cause problems during the execution of the script, execution is not halted. 
> I thought I had set the line-wrap to 120 in ST2. I'll look into it later and see if I can fix the auto line-wrapping.
> 
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